All codes › P0036
P0036: HO2S Heater Control Circuit (Bank 1 Sensor 2)
What it means
The heater circuit for the bank 1 downstream O2 sensor (after the cat) has an electrical fault.
Severity: Low Downstream heater fault only affects emissions monitoring.
Common causes
- Failed downstream O2 sensor heater
- Blown fuse
- Corroded connector under the car
- Damaged wiring
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Often DIY. The downstream sensor is under the car behind the cat; penetrating oil helps.
Repair cost
SEEDED ESTIMATE Roughly $70–$330
Most likely repair: oxygen sensor. Diagnosis fees, taxes and other causes are not included.
| Line | Low | High | Basis |
|---|---|---|---|
| Oxygen sensor | $36 | $168 | Typical listed retail range, source |
| Labor 0.3–1 hr | $30 | $160 | $100–$160/hr, shop survey |
⚠️ This is an editorial placeholder range for this type of repair. It is not based on real invoices or licensed pricing data yet. Real ranges will appear here once enough reader invoices for P0036 are verified.
Verified reader invoices for P0036: 0. Share your repair bill to help build real costs.
Tools that can read P0036
- ScanFixAI: Pro $29.99/mo or $249.99/yr
- OBDAI: Annual PRO bundle $299
- BlueDriver Pro Next-Gen: $119.95 list ($99.95 sale seen)
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